Pain
Rebecca Howard, MD
Resident Physician
Department of Rehabilitation and Human Performance, Icahn School of Medicine at Mount Sinai
Long Island City, New York, United States
Alexandra Canori, PhD
Postdoctoral Research Fellow
Department of Rehabilitation & Human Performance, Icahn School of Medicine at Mount Sinai
New York, New York, United States
Laura Tabacof, MD
Assistant Clinical Professor
Icahn School of Medicine at Mount Sinai
New York, New York, United States
David Putrino, PhD
Director of Rehabilitation Innovation
Icahn School of Medicine at Mount Sinai
New York, New York, United States
Rebecca Howard, MD
Icahn School of Medicine at Mount Sinai
New York, New York, United States
This retrospective study investigated the effects of repetitive transcranial magnetic stimulation (rTMS) on neuropathic pain severity.
Design:
Patients were 18 years or older with neuropathic pain for at least 3 months with a primary origin. Exclusion criteria included severe pain of other origin (e.g. musculoskeletal pain), psychiatric disorders, brain stimulation risk factors, and medical instability. rTMS was delivered using a MagPro X100 stimulator at 20Hz frequency over the primary motor cortex for five consecutive days at 90% resting motor threshold/total of 2000 pulses. Pain visual analog scale (VAS) was recorded at baseline, immediately after treatment completion (post), 1-week (FU1) and 6-weeks (FU2) after treatment completion.
Results:
Twelve patients were included (50% male, 50% female, mean age 68) with etiologies of neuropathic pain including spinal cord injury, stroke, and peripheral neuropathy. Baseline VAS was negatively correlated to percent change in VAS at FU1 and FU2 (FU1: r = -0.764, p-value= 0.004; FU2: r= -0.787, p-value= 0.002). The number of pain medication classes was positively correlated to percent change in VAS at FU2 (FU2: r= 0.698, p-value= 0.012). Pain decreased between baseline and post (t= -4.81, p.adj=0.003), as well as between baseline and FU1 (t= -3.29, p.adj=0.043); and increased between post and FU2 (t= 3.23, p.adj= 0.049).
Conclusions:
Results suggest that higher baseline pain scores may lead to larger relative pain reduction following rTMS. Additionally, higher numbers of medications at rTMS initiation may predict worse pain at longer term follow-up. Overall, results demonstrate a potential benefit of rTMS on chronic neuropathic pain lasting between 1 week and 6 months. More research is needed to further elucidate the characteristics that may predict neuropathic pain response to rTMS and to support the current limited evidence on durability of treatment.
